Fix #177358: Link options by node

Fix #247578: Print URLs by content type
Fix #298063: Most printed, emailed and PDFd blocks
Fix #333049 and #333957: Add ability to change user-visible strings in the settings pages
Use different teaser comparison
Try to fix #336865: also replace the opening <p>
Fix content corner problem and other minor fixes
Add ability to configure link text strings
Improve variable cleanup at uninstall